
(5, 8) and (-2, 12)

𝑦 = 5𝑥 − 2

3𝑥 − 4𝑦 = 20



Snow is 0.02 m deep after 1 hour and 0.06 m
deep after 3 hours.
A car is 200 km from its destination after 1
hour and 80 km from its destination after 3
hours.
10 sec
2 miles
15 sec
3 miles

The ratio of two variables is constant.

Represented: 𝑦 = 𝑘𝑥, 𝑘 ≠ 0

𝑘 is called the constant of variation
 𝑘=
𝑦
𝑥
 7𝑦
= 3𝑥
 2𝑥
− 4𝑦 = 8
 5𝑥
− 2𝑦 = 0
 8𝑥
+𝑦 =3



Write a direct variation equation for the distance 𝑑
flown in time 𝑡.
Graph the equation
Estimate how many hours it will take for an airliner
to fly 6500 miles.



Write an equation that related weight, in pounds on
Earth (x) and on Mars (y).
Graph the equation
Estimate how much a 180 lb man on Earth will
weight on Mars.
x
4
8
10
y
6
12
15
x
-2
1
4
y
3.2
2.4
1.6

Worksheet